class Nstr(str):
    def __init__(self,str1=''):
        if isinstance(str1,str):
            self.total=0
            for each_self in self:
                self.total += ord(each_self)
        else :
            print('参数错误')
    def __add__(self,other):
        return self.total+other.total
    
    def __sub__(self,other):
        return self.total-other.total

    def __mul__(self,other):
        return self.total*other.total

    def __truediv__(self,other):
        return self.total/other.total
    
    def __floordiv__(self,other):
        return self.total//other.total

a = Nstr('FishC')
b = Nstr('love')
